. >> there's science to it. >> there's heavy science and we tell you all about it in the book. >> we know what happens when we eat junk food. we get father, but what happens inside the body? >> a lot of things happen. we eat too much we gain fat and it's toxic. it surrounds our vital organs causes a toxic disease. it's killing us. >> there's two things here what you eat and what you do with your body. what's going on, chris, with our body and what does it take to cement that habit? >> one of the nice things about the book nice guys don't talk about exercise a lot. we talk about it all the time. it's the flywheel of maintenance. it does all kinds of stuff to help you lose weight be healthier, more optimistic or more energetic. we told people it makes a world of sense to work out semi hard six days a week. people go, what? way too scarey. but you have to do it. >> weight's become a bad buzzsquoorks . >> wheat's become a bad buzz world. >> 1% of the americans have celiac disease and they can't have wheat in their diet. i think it's easy for us to say, hey, we can't eat wheat products. i